public Polygon3D Vs_polygon_clip_2d(Polygon3D poly)
{
Polygon3D s = new Polygon3D();
Polygon3D r = new Polygon3D();
double vxmin = vp_xmin - 0.40000000000000002D;
double vymin = vp_ymin - 0.40000000000000002D;
double vxmax = vp_xmax + 0.40000000000000002D;
double vymax = vp_ymax + 0.40000000000000002D;
s.SetPol(poly);
double xmin = poly.XMin();
double xmax = poly.XMax();
double ymin = poly.YMin();
double ymax = poly.YMax();
if (xmax < vxmin || xmin > vxmax || ymax < vymin || ymin > vymax)
{
return(r);
}
if (xmin >= vxmin && xmax <= vxmax && ymin >= vymin && ymax <= vymax)
{
r.SetPol(poly);
return(r);
}
if (xmin >= vxmin)
{
r.SetPol(s);
}
else
{
for (int i = 0; i < s.NVertex(); i++)
{
int j;
if (i == s.NVertex() - 1)
{
j = 0;
}
else
{
j = i + 1;
}
double xi = s.GetVertex(i).x;
double yi = s.GetVertex(i).y;
double xj = s.GetVertex(j).x;
double yj = s.GetVertex(j).y;
if (xi >= vxmin)
{
r.AddVertex(new Vector3D(xi, yi, 0.0D));
if (xj < vxmin)
{
r.AddVertex(new Vector3D(vxmin, yi
+ ((yj - yi) * (vxmin - xi)) / (xj - xi), 0.0D));
}
}
else if (xj >= vxmin)
{
r.AddVertex(new Vector3D(vxmin, yi
+ ((yj - yi) * (vxmin - xi)) / (xj - xi), 0.0D));
}
}
}
s = new Polygon3D();
if (ymin >= vymin)
{
s.SetPol(r);
}
else
{
for (int i_0 = 0; i_0 < r.NVertex(); i_0++)
{
int j_1;
if (i_0 == r.NVertex() - 1)
{
j_1 = 0;
}
else
{
j_1 = i_0 + 1;
}
double xi_2 = r.GetVertex(i_0).x;
double yi_3 = r.GetVertex(i_0).y;
double xj_4 = r.GetVertex(j_1).x;
double yj_5 = r.GetVertex(j_1).y;
if (yi_3 >= vymin)
{
s.AddVertex(new Vector3D(xi_2, yi_3, 0.0D));
if (yj_5 < vymin)
{
s.AddVertex(new Vector3D(xi_2 + ((xj_4 - xi_2) * (vymin - yi_3)) / (yj_5 - yi_3), vymin, 0.0D));
}
}
else if (yj_5 >= vymin)
{
s.AddVertex(new Vector3D(xi_2 + ((xj_4 - xi_2) * (vymin - yi_3)) / (yj_5 - yi_3), vymin, 0.0D));
}
}
}
r = new Polygon3D();
if (xmax <= vxmax)
{
r.SetPol(s);
}
else
{
for (int i_6 = 0; i_6 < s.NVertex(); i_6++)
{
int j_7;
if (i_6 == s.NVertex() - 1)
{
j_7 = 0;
}
else
{
j_7 = i_6 + 1;
}
double xi_8 = s.GetVertex(i_6).x;
double yi_9 = s.GetVertex(i_6).y;
double xj_10 = s.GetVertex(j_7).x;
double yj_11 = s.GetVertex(j_7).y;
if (xi_8 <= vxmax)
{
r.AddVertex(new Vector3D(xi_8, yi_9, 0.0D));
if (xj_10 > vxmax)
{
r.AddVertex(new Vector3D(vxmax, yi_9 + ((yj_11 - yi_9) * (vxmax - xi_8)) / (xj_10 - xi_8), 0.0D));
}
}
else if (xj_10 <= vxmax)
{
r.AddVertex(new Vector3D(vxmax, yi_9 + ((yj_11 - yi_9) * (vxmax - xi_8)) / (xj_10 - xi_8), 0.0D));
}
}
}
s = new Polygon3D();
if (ymax <= vymax)
{
s.SetPol(r);
}
else
{
for (int i_12 = 0; i_12 < r.NVertex(); i_12++)
{
int j_13;
if (i_12 == r.NVertex() - 1)
{
j_13 = 0;
}
else
{
j_13 = i_12 + 1;
}
double xi_14 = r.GetVertex(i_12).x;
double yi_15 = r.GetVertex(i_12).y;
double xj_16 = r.GetVertex(j_13).x;
double yj_17 = r.GetVertex(j_13).y;
if (yi_15 <= vymax)
{
s.AddVertex(new Vector3D(xi_14, yi_15, 0.0D));
if (yj_17 > vymax)
{
s.AddVertex(new Vector3D(xi_14 + ((xj_16 - xi_14) * (vymax - yi_15)) / (yj_17 - yi_15),
vymax, 0.0D));
}
}
else if (yj_17 <= vymax)
{
s.AddVertex(new Vector3D(xi_14 + ((xj_16 - xi_14) * (vymax - yi_15)) / (yj_17 - yi_15), vymax, 0.0D));
}
}
}
return(s);
}